Question

我写了下面的查询，它设计了产品总数乘以数量价格并将其放入新列。我在想什么，有点困惑。那么还有一种方法可以完成这个新专栏。因此，除了获得订购的每一行的总数之外，我还可以获得订单本身的总数。

SELECT Product_Quantity, ProductPrice, (Product_Quantity*ProductPrice) as   Total FROM Order_Info WHERE Order_Number = '1'

Answer 1

这会添加一个总记录。使用ROLLUP模拟GROUP BY

SELECT
  Product_Quantity
, ProductPrice
, (Product_Quantity*ProductPrice) AS Total
FROM
 Order_Info
WHERE
 Order_Number = '1'

UNION ALL

SELECT
  NULL
, NULL
, SUM((Product_Quantity*ProductPrice)) AS Total
FROM
 Order_Info
WHERE
 Order_Number = '1'

Answer 2

要获取摘要行，您可以使用sql的union和sum聚合函数。试试这个：

SELECT Product_Quantity, ProductPrice, (Product_Quantity*ProductPrice) as   Total FROM Order_Info WHERE Order_Number = '1'
union all
SELECT sum(Product_Quantity), sum(ProductPrice), sum(Product_Quantity*ProductPrice) as   Total FROM Order_Info WHERE Order_Number = '1'

MySQL查询问题 - 添加额外和总计

2 个答案: